package recursion.nowcoder.easy;

import java.util.Scanner;

/**
 * @author bruin_du
 * @description 养兔子
 * https://www.nowcoder.com/questionTerminal/71d3849a19f04a1591c415964ac148f1
 * @date 2022/6/2 16:43
 **/
public class RaiseARabbit {
    public static void main(String[] args) {
        long[] arr = new long[91];
        arr[0] = arr[1] = 1;
        for (int i = 2; i < arr.length; i++) {
            arr[i] = arr[i - 1] + arr[i - 2];
        }
        Scanner in = new Scanner(System.in);
        while(in.hasNextInt()){
            int n = in.nextInt();
            System.out.println(arr[n]);
        }
    }
}
